[4.02] A Capture Scenario for Globular Cluster Omega Centauri

Recent advances in understanding the nature of omega
Centauri - the most massive Milky Way globular cluster -
have now placed on a firmer ground its accretion origin as
opposed to formation within the Milky Way. Unlike the
majority of the Milky Way globular clusters, omega Cen is a
complex chemical system with an extended star-formation
history.

We explore an accretion origin for omega Cen by N-body
modeling of the orbital decay and disruption of a Milky-Way
dwarf satellite. We find that a capture scenario can produce
an omega Cen-like object with the current low energy orbit
of the cluster. Our best model is a nucleated dwarf galaxy
with a Hernquist density profile that has a mass of 8 x
109 M\odot, and a half-mass radius pf 1.4 kpc.